1. Field
The present disclosure generally relates to structures and fabrication processes associated with bipolar transistors.
2. Description of the Related Art
A bipolar junction transistor (BJT) typically includes two back-to-back p-n junctions formed by a base region disposed between an emitter region and a collector region. Such junctions can include a PNP configuration or an NPN configuration. The bipolar functionality results from its operation involving both electrons and holes.
A heterojunction bipolar transistor (HBT) is a type of BJT, where different semiconductor materials are utilized for the emitter and base regions to yield a heterojunction. Such a configuration can allow HBTs to be particularly useful in radio-frequency (RF) applications, including high-efficiency RF power amplifiers.